Reinforced concrete structure



Sept. 12, 1950 J. M. CROM REINFORCED CONCRETE STRUCTURE Filed May 1, 1946 6 Q o o o O O o O 0 O O O O O o o O o o O O o O o JO JL Z from Patented Sept. 12, 1950 K EiiNFoRoEwooNoRETii s'rnocruns 2 Delaware John-.lVLl-Grom; Washington, D. 0., assignor to reload. Enterprises, Inc a corporation on,

Application-*Mayn1946,s eriaflfiojdfiimtf comma invention" relates/ to a reinforced concrete structures: andwmore; particularly to reinforced cylindrical concrete structures of the nature of reinforced. concrete pipe 1 sections,; reinforced concretetank sections and other reinforced concrete constructions of; a. generally cylindrical shape.

Prior to, this inventiorn cylindrical concrete structures have been reinforced by steel members extending either longitudinally, circumferentially on bot-h In some cases these reinforcing men);-

bers have been placed under stressso that they tendtoaexert a compressive force on the concrete and; thereby more effectively. prevent its cracking.

or breaking. a H Sincecylindricahconcrete structures are usually subjected both to radial stresses and to longitudinal stresses, it has heretoforebeen necessary in order to reinforce the concrete structuresagainst both these" stresses to" incorporate in such 'st'r'uctures both longitudinally extending andcircuni ferentially eiiten'ding reinforcing rriembers.

In accordance with the principles of this invena tion; it has been found possible toiincorporate in cylindrical concrete structuresa single; type: of reinforcing, which reinforcing adequately; reinre s t e dr a c epreies rue ag i h adia -"a o tud n t esse Briefly, the present 'nventon comprlses the mo ci .Q c n et 53 912 4 352, f EQQQ'M Y cylindrical shape by the incorporationtherein of a basket or double-helically wound reinforcing material so positioned as to provide both longitudinal and radial strength. Preferably, the reinforcing material is steel wire and is wound onto the cylindrical concrete structure at such an angle that it provides the desired ratio between longitudinal reinforcing and radial reinforcing. For example, if a reinforcing wire were wound onto the cylindrical concrete object so that there was no appreciable angle between the wire and a plane normal to the longitudinal axis of the concrete structure, the wire would provide radial support or reinforcement, but would provide substantially no longitudinal reinforcement. Similarly, if the wire were placed in the concrete structure in a direction parallel to the longitudinal axis thereof, it would provide longitudinal reinforcement, but substantially no radial reinforcement. It has been found, for most purposes, that if the wire is wound on the concrete structure at an angle of approximately 20 to a plane normal to the longitudinal axis, it will provide the proper distribution between longitudinal and radial reinforcement.

The present invention further contemplates the (Cl. Bile-84?)- application of the reinforcing material in a pro tensione'd: state;. that is, it contemplates that the wire-or other reinforcing material shall 'be'wound onto? the concrete structure under a predeter 5 mined tension and'iwill thereby providemore e'fli cient and more satisfactoryreinforcement; This. invention further contemplates the covering of the reinforcing material, once'itt is int place on the concretestructurawith a coating or covering of somelprotective material such as. additional con crete or asphalt. In some instances it maybe. found desirable tocoat the reinforcing. material: itself-with asphaltor some similarsmaterialprior; to;- its application to the pip'e so'that; it will-be" 151 free to move slightly with relationxto'thel'pipe and thus: equalize the tension; at" various pOifitSrOn the: surface-pf the cylindricalstructure. I Further details. and advantages of this inven tion may be ascertained from; a. consideratidnofe 2c: theappended drawingsrand the following detailed descri tion of the pref erred; embodiment of ithi'si invention .as illustrated and: described therein; I n-the=drawings:-.. V. v.

Ffigure a side elevational view,..-partly'in:. -section,. of. apiece of concrete pipe constructed in. accordance with the principles oft-this inyenl j w w: ,lijigure 2 isa detailyiewon a; somewhat larger. eia e-efa-p r .o the c mre am ecf F ured; y and Figure 3 is a cross-sectional viewtaken on lines 3-3 of Figure 2.

As illustrated in Figure 1, a concrete pipe section may comprise an elongated cylindrical portion II] with a collar ii integrally formed at one end thereof for the purpose of attaching the pipe section to an adjacent section. Such a pipe section, in accordance with the principles of this invention, may comprise a concrete pipe base I2 40 wound with a steel reinforcing wire l3 and covered by an outer coating M of concrete or some other material. The reinforcing wire I3 may be wound on the pipe in the form of a continuous double helix in which the wire progresses continuously around the pipe and at the same time continuously from the top and the bottom of the pipe and back again. By starting at the bottom of the pipe at an arbitrary point, which may be designated as i5, and proceeding to wind the wire around and up the pipe to the top and then continuing to wind the wire around and down the pipe back to the bottom, and then repeating this process until the pipe is completely covered by a series of double helices of wire, it has been found that a collar II into the upper part of the pipe section Hi to provide the necessary reinforcing in the collar 1 l and throughout the area where the collar ll joins the pipe section It.

Preferably, a predetermined amount of tensionis applied to the reinforcing wire l3 and also to the pipe. By properly coordinating the longitudinal motion and the rotational motion, the wire may be wound onto the pipe at any desired angle. An angle of 20 to a plane perpendicular to the longitudinal axis of the pipe has been found satisfactory for most purposes, but this can be varied as desired for any particular concrete structure. g In most cases, however, an angle of between and 30 will be found satisfactory and angles outside of this range will be found to pro- -vide a less desirable distribution of the reinforcethe reinforcing wire i6 during its application to the pipe and, if desired, asphaltor the like may be applied to the reinforcing wire to give it a certain freedom of movement with respect to the Pip In most cases, it will be found desirable to cover the reinforcing wire with an additional coating of concrete or asphalt or some other material [-4 was to protect the reinforcing wire from exposure to the elements.

A particularly desirable manner of anchoring the/reinforcing wire l3 in the places where it changes direction at the top and bottom of the pipe is illustrated in Figures 2 and 3. The concrete pipe base [2 is usually precast and it is relatively simple in the process of precasting this concrete type base to cast thereon a series of lugs H at the time the pipe is cast. These lugs may be of almost any desired shape but preferably are of the shape shown in Figures 2 and 3 so that they expediently catch and hold the reinforcing wire l3 as it reaches the end of its lateral travel and reverses its direction,

' With such lugs cast on the concrete pipe base I2, the reinforcing wire i3 may be rather easily wound onto the pipe base by either placing the pipe on a rotating standard and feeding the wire onto the pipe while rotating the pipe, or rotating the'wire applying device around the pipe while the pipe itself is held stationary. During'the application of the wire, it is, of course, necessary Number' Name Date I 840,293 Bocquet Jan. 1, 1907 939,567 A Thun Nov. 9, 1909' 1,008,209 Skinner Nov. 7, 1911 1,775,334 Wanamaker Sept. 9, 1930 2,236,108 Miller et al Mar. 25, 1941 2,280,252 Muehleck Apr. 21, 1942 2,348,477

ment.

What is claimed is:

1. A radially and axially reinforced hollow cylindrical concrete structure adapted to withstand internal pressure that comprises a hollow cylindrical concrete base member, a prestressed reinforcing material wound onto the outer surface thereof and forming a series of helices thereon, some of which helices slope in one direction and'some of which slope in the opposite direction,

and a concrete coating covering said reinforcing material.

2. A radially and axially reinforced, hollow,"

cylindrical,-concrete structure adapted to withstand internal pressure, that comprises a hollow, cylindrical, concrete base member, a prestressedreinforcing material forming a series of helices'on the outer surface thereof, some of which helices slope in one direction at an angle of between 15 and 30 to a plane perpendicular to a I REFERENCES CITED The following references are of record in file'j'of this patent; v

. UNITED STATES PATENTS at sub- Jenkins May 9, 1944 

